Novavax Reports Positive Data for its Trivalent Seasonal Influenza (VLP) Vaccine Candidate in a Second Phase II Study

Novavax Reports Positive Data for its Trivalent Seasonal Influenza (VLP)
Vaccine Candidate in a Second Phase II Study
- Results Presented at 47th Annual Meeting of the Infectious Diseases Society
of America

ROCKVILLE, Md., Nov. 2 /PRNewswire-FirstCall/ -- Novavax, Inc. (Nasdaq: NVAX)
a clinical-stage vaccine company, announced today that the Company made a
poster presentation on the "Safety and Immunogenicity of a Recombinant
Trivalent Seasonal Influenza Virus-like Particle (VLP) Vaccine in Healthy
Adults" on Saturday, October 31, 2009 at the 47(th) Annual Meeting of the
Infectious Diseases Society of America (IDSA).

This presentation included data from a study of Novavax's trivalent seasonal
influenza VLP vaccine that began in May of this year among healthy adults 18
to 49 years of age. The vaccine contained VLPs matched to the influenza
strains recommended for the 2008-2009 influenza vaccine including H1N1
A/Brisbane/59/2007, H3N2 A/Brisbane/10/2007, and B/Florida/04/2006. The study
enrolled 241 subjects in total, including 221 who were randomized to receive
either VLP vaccine at 15 mcg or 60 mcg or a placebo and 20 subjects who
received an inactivated influenza vaccine (TIV).

The trivalent seasonal influenza VLP vaccine was well tolerated and
immunogenic. The incidence of adverse events was comparable in the VLP
vaccine groups (10.6%) and the placebo group (11.8%). No serious
vaccine-related adverse events have been reported to date. The VLP vaccine
induced robust hemagglutination inhibition (HAI) antibody responses against
all three strains in the vaccine and a drifted strain. Seroconversion
(greater than or equal to 4-fold rise in titer from baseline) rates met the
suggested FDA criteria for licensure of seasonal influenza vaccines for all
three strains. For subjects in the 15 mcg group, seroconversion rates (95%
CIs) were 57% (44, 68), 86% (75,93), and 62% (50,74) against the H1N1, H3N2,
and B strains, respectively. Seroprotection (titer greater than or equal to
1:40) rates met the FDA criteria for licensure for all strains except the H1N1
strain. For subjects in the 15 mcg group, seroprotection rates (95% CIs) were
67% (54,78), 91% (82,97), and 84% (73,92) against the H1N1, H3N2, and B
strains, respectively. Interestingly, the FDA seroconversion and
seroprotection criteria were also met for a drifted H3N2 strain,
A/Wisconsin/67/05, which was included in the 2006-2007 influenza vaccine. The
seroconversion and seroprotection rates against this strain were 77% and 93%,
respectively, among subjects in the 15 mcg group.

Antibody responses were observationally compared among VLP vaccine and TIV
recipients although the sample size for the TIV group was too small to support
definitive conclusions. In this small study, HAI responses against the H1N1
and B strains were statistically indistinguishable and HAI responses against
the H3N2 A/Brisbane strain appeared higher in VLP as compared with TIV
recipients. These results support moving forward with a larger head-to-head
study of the VLP vaccine as compared with TIV.

In addition to the HAI responses, although not presented in the poster,
functional antibody against the Neuraminidase enzyme was measured in the sera
of immunized subjects using a neuraminidase inhibition assay (NAI) developed
by Novavax scientists. Inhibition of neuraminidase activity may be important
in reducing the spread of influenza virus down the respiratory tract and
severe influenza disease. Preliminary data indicate that the trivalent
seasonal influenza VLP vaccine induced functional antibody that inhibits
neuraminidase activity of Types A and B influenza viruses.

"We are pleased with the results of this study, which support continued
development of novel VLP vaccines against influenza and moving forward with
our head-to-head study in the elderly population this Fall," said Dr. Rahul
Singhvi, President and Chief Executive Officer of Novavax. "We believe that
our VLP influenza vaccine has the potential to induce broad immunity against
influenza including cross-reactivity against drifted strains which may emerge
throughout an influenza season," said Dr. Singhvi.

Seasonal Influenza
Globally, seasonal flu infects between 5 percent and 20 percent of the
population and kills between 250,000 and 500,000 people each year. In the US,
the Centers for Disease Control and Prevention reports that 15 to 60 million
people contract influenza each year leading to over 200,000 hospitalizations
and 36,000 deaths. The Advisory Committee on Immunization Practices ("ACIP")
currently recommends seasonal influenza vaccination for children six months
through 18 years of age, pregnant women, and adults over 50 years of age, and
individuals of any age with chronic health conditions or who are at high risk
of influenza disease. Based on the expanding recommendation of vaccination to
new age groups, the growing worldwide population to be vaccinated, and the
need of an improved influenza vaccine for the elderly, global market
projections of seasonal influenza are estimated to increase from $2.8 billion
in 2007 to $6.5 billion by 2013.

About VLPs
Virus-like particles (VLPs) mimic the external structure of viruses but lack
the live genetic material that causes viral replication and infection. VLPs
can be designed quickly to match individual viral strains and be produced
efficiently using portable cell-culture technology. Novavax VLP-based vaccine
candidates are produced more rapidly than egg-based vaccines by using
proprietary, portable, recombinant cell-culture technology.

About Novavax
Novavax, Inc. is a clinical-stage biotechnology company, creating novel
vaccines to address a broad range of infectious diseases worldwide, including
H1N1, using advanced proprietary virus-like-particle (VLP) technology. The
company produces potent VLP-based, recombinant vaccines utilizing new and
efficient manufacturing approaches. Novavax is committed to using its VLP
technology to create country-specific vaccine solutions. It recently launched
a joint venture with Cadila Pharmaceuticals, named CPL Biologicals, to develop
and manufacture vaccines, biological therapeutics and diagnostics in India.
Additional information about Novavax is available on the company's website:
www.novavax.com.

Forward-Looking Statements
Statements herein relating to future financial or business performance,
conditions or strategies and other financial and business matters, including
expectations regarding clinical trials and development of the 2009 H1N1
vaccine, the potential use of any data from clinical trials and other
anticipated milestones are forward-looking statements within the meaning of
the Private Securities Litigation Reform Act. Novavax cautions that these
forward-looking statements are subject to numerous assumptions, risks and
uncertainties, which change over time. Factors that may cause actual results
to differ materially from the results discussed in the forward-looking
statements or historical experience include risks and uncertainties, including
clinical trial results, which may not be sufficient for regulatory approval or
may indicate safety concerns not yet encountered; even if the results of the
planned clinical trial are positive, the data may not be accepted by
regulatory bodies in other countries or the 2009 H1N1 vaccine may not be
approved by the Mexican government or additional clinical trials may be
required; if approved, approval of the 2009 H1N1 vaccine may not be timely and
thus may not be granted until after the 2009/2010 flu season has ended; sales
of the 2009 H1N1 vaccine are not scheduled to begin until late in the
2009/2010 flu season which could result in poor sales; Avimex is expected to
be responsible for sales of the 2009 H1N1 vaccine in Mexico, thus, the Company
would be dependent on Avimex's sales effort; the Company has not yet
manufactured, or relied on third parties to manufacture, any vaccines at a
commercial scale; the 2009 H1N1 vaccine must be manufactured in a short period
of time and will be subject to scale-up, validation and inspection;
competition from already approved vaccines for the 2009 H1N1 flu; business
abilities and judgment of personnel and corporate partners; and the
availability of qualified personnel. Further information on the factors and
risks that could affect Novavax's business, financial conditions and results
of operations, is contained in Novavax's filings with the U.S. Securities and
Exchange Commission, which are available at www.sec.gov. These forward-looking
statements speak only as of the date of this press release, and Novavax
assumes no duty to update forward-looking statements.

SOURCE Novavax, Inc.

Tricia J. Richardson of Novavax, Inc., +1-240-268-2031